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An absolutely secure QKD scheme with no detection noise, entanglement and classical communication

Janos A. Bergou·Laszlo B. Kish
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Abstract

A new quantum communication scheme is introduced which is the quantum realization of the classical Kish-Sethuraman (KS) cipher. First the message is bounced back with additional encryption by the Receiver and the original encryption is removed and the message is resent by the Sender. The mechanical analogy of this operation is using two padlocks; one by the Sender and one by the Receiver. We show that the rotation of the polarization is an operator which satisfies the conditions required for the KS encryption operators provided single photons are communicated. The new method is not only simple but has several advantages. The Evasdropper extracts zero information even if she executes a quantum measurement on the state. The communication can be done by two publicly agreed orthogonal states. Therefore, there is no inherent detection noise. No classical channel and no entangled states are required for the communication.

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Janos A. Bergou, Laszlo B. Kish. 2005-09-15. An absolutely secure QKD scheme with no detection noise, entanglement and classical communication. https://arxiv.org/abs/quant-ph/0509097

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